package com.atguigu.gulimall.product.web;

import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import com.atguigu.gulimall.product.vo.Catelog2Vo;
import org.redisson.api.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.TimeUnit;


@Controller
public class IndexController {

    @Autowired
    CategoryService categoryService;

    @Autowired
    RedissonClient redisson;

    @Autowired
    StringRedisTemplate redisTemplate;
    @GetMapping({"/","/index.html"})
    public String indexPage(Model model){

        //TODO 1.查询出所有的1级分类
        List<CategoryEntity> categoryEntities = categoryService.getLevel1Categorys();


        //视图解析器进行拼接：
        // classpath:/templates/ +返回值+ .html
        model.addAttribute("categorys",categoryEntities);
        return "index";
    }

    //index/catalog.json
    @ResponseBody
    @GetMapping("/index/catalog.json")
    public  Map<String, List<Catelog2Vo>> getCatalogJson(){
        Map<String, List<Catelog2Vo>> map = categoryService.getCatalogJson();
        return map;
    }

    @ResponseBody
    @GetMapping("/hello")
    public String hello(){
        //获取同一把锁，只要锁的名字一样，就是同一把锁
        RLock lock = redisson.getLock("mylock");
        //加锁
//        lock.lock();//阻塞式等待 30s
        lock.lock(10, TimeUnit.SECONDS);//10秒后自动关闭
        //问题：lock.lock(10,TimeUnit.SECONDS);在锁时间到了以后，不会自动续期
        //1.如果我们传递了锁的超时时间，就发送给redis执行脚本，进行占锁，默认超时就是我们指定的时间
        //2.如果我们未指定锁的超时时间，就是用30*1000[LockWatchdogTimeout]看门狗的默认时间
        //只要占锁成功，就会启动一个定时任务(重新给锁设置过期时间，新的过期时间就是看门狗的默认时间)每隔十秒自动续期
        //internalLockLeaseTime / 3
        //最佳实战
        //lock.lock(10, TimeUnit.SECONDS);//10秒后自动关闭 省掉了整个续期操作，手动解锁

        try {
            System.out.println("加锁成功，执行业务。。。" + Thread.currentThread().getId());
            Thread.sleep(30000);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        } finally {
            //解锁
            System.out.println("释放锁。。。" + Thread.currentThread().getId());
            lock.unlock();
        }
        return "hello";
    }

    //保证一定能读到最新数据，修改期间，写锁是一个排他锁(互斥锁)，读锁是一个共享锁
    //写锁没释放读就必须等待
    //读+读：相当于无锁，并发读，只会在redis中记录好，所有当前的读锁，他们都会同时加锁成功
    //写+读：等待写锁释放
    //写+写：阻塞方式
    //读+写：有读锁，写锁也需要等待
    //只要有写的存在，都必须等待
    @ResponseBody
    @GetMapping("/write")
    public String writeValue(){
        String s = "";
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        RLock rLock = lock.readLock();
        try {
            //1.改数据加写锁，读数据加读锁
            //加锁
            rLock.lock();
            s = UUID.randomUUID().toString();
            Thread.sleep(30000);
            redisTemplate.opsForValue().set("writeValue", s);
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        } finally {
            //解锁
            rLock.unlock();
        }
        return s;
    }

    @ResponseBody
    @GetMapping("/read")
    public String readValue(){
        String s = "";
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        RLock rLock = lock.writeLock();
        rLock.lock();
        try {
            s = redisTemplate.opsForValue().get("writeValue");
        } catch (Exception e){
            e.printStackTrace();
        } finally {
            rLock.unlock();
        }
        return s;
    }

    /**
     * 放假，1班没人，5个班全部走完，关闭大门
     */
    @ResponseBody
    @GetMapping("/lockDoor")
    public String lockDoor() throws InterruptedException {
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.trySetCount(5);
        door.await();//等待闭锁都完成

        return "放假了。。。";
    }

    @GetMapping("/gogogo/{id}")
    @ResponseBody
    public String gogogo(@PathVariable("id") Long id){
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.countDown();//计数减一，相当于走空一个班级

        return id + "班的人都走光了。。。。";
    }

    /**
     * 车库停车，3个车位
     */
    @ResponseBody
    @GetMapping("/park")
    public String park() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        boolean b = park.tryAcquire();
        park.acquire();//获取一个信号，获取一个值，占一个车位
        if(b){
            //执行业务
        }else {
            //限流
        }
        return "ok>" + b;
    }

    @ResponseBody
    @GetMapping("/go")
    public String go() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        park.release();//释放一个车位

        return "ok";
    }
}
